The invention relates to a device for the manufacture of hollow articles out of plastics, especially thermoplastics, e.g., by the blow molding process, consisting of several hollow-mold parts, which take up a preform for the blowing process, whereby at least one hollow-mold part is movably disposed on a spar guide, and whereby locking devices are provided at the hollow-mold parts.
For the manufacture of hollow articles out of thermoplastic synthetics through the blowing up of the preform in the blowing device there are known mold locking systems that have in each corner of the mold clamping plates, that is a total of four locking spars, in order to obtain a uniform distribution of force over the locking frame. Such a four-spar locking system ensures, to be sure, an optimal closure of the hollow-mold parts while the blowing process is carried out, but greatly impedes the charging of the blowing devices with preforms and the ejection of the finished molded articles.
From the West German patent publication DT-OS 24 28 914 is also already known a device for the manufacture of hollow articles of thermoplastic synthetics, whereby the movable mold carriers for the hollow mold are carried by two spars disposed underneath the hollow mold. The spars are thereby exclusively disposed at the lower portion of the locking frame. This arrangement is said to render it possible that the space between the mold carriers in which is disposed the split cavity mold, remains far-reachingly freely accessible when the hollow mold is open, so that larger molded articles are claimed to be freely removable after the opening of the hollow mold without impediment by spars before the hollow mold is moved away.
In practice this is, however, not the case because the second spar causes especially in the case of elongated preforms, a considerable restriction of the feeding possibilities of the preform. Furthermore, an additional locking mechanism is required.
The invention has the task to indicate a principle of design for the initially mentioned devices with which are created optimal spatial conditions for the charging of the blowing devices with preforms. This task is solved in accordance with the invention in that, that the spar guide consists of only one spar with guide part.